Apparatus for suspending a conductor from an insulator



O July 12, 1966 M. BETHEA, JR 3,260,795

APPARATUS FOR SUSPENDING A CONDUCTOR FROM AN INSULATOR Filed Jan. 13, 1965 INVENTOR.

MA L601. 5 ran-15mm MyW ATTORNEYS United States Patent 3,260,795 APPARATUS FOR SUSPENDING A CONDUCTOR FROM AN INSULATOR Malcolm Bethea, Jr., P.O. Box 1407, Birmingham, Ala. Filed Jan. 13, 1965, Ser. No. 425,216 4 Claims. (Cl. 174-144) This invention relates to suspension apparatus for conductors and more particularly to apparatus for supporting power transmission lines, such as bundled conductors.

An object of my invention is to provide suspension apparatus for conductors in which a relatively wide, downwardly opening shell-like yoke body is provided having a convexly curved outer surface whereby corona and radio noise voltages are reduced greatly without employing auxiliary shielding or other gradient control devices.

Another object of my invention is to provide apparatus for suspending a conductor from an insulator string whereby the electric stress distribution is such that the line voltage is divided between the insulators in a more uniform manner.

A further object of my invention is to provide apparatus for suspending a conductor from an insulator in which improved mechanical strength properties as well as improved electrical properties are obtained.

A still further object of my invention is to provide suspension apparatus -for conductors of the character designated which shall be simple of construction, economical of manufacture and which shall be adapted for supporting various types of bundle conductors and the like.

I have found from actual practice and from electrical tests that better distribution of electrical stresses on the insulators is obtained with my improved apparatus; the yoke is made relatively free from corona and radio influence voltage is decreased at relatively high line-toground voltages; the suspension clamps carried by the shell-like yoke are protected due to the shape of the yoke; and improved mechanical strength properties and electrical properties are obtained in a more economical manner.

Suspension apparatus for conductors embodying features of my invention is illustrated in the accompanying drawing, forming a part of this application, in which:

FIG. 1 is a side elevational view of the suspension apparatus, partly broken away and in section;

FIG. 2 is an end elevational view, partly broken away and in section; and,

FIG. 3 is a graph showing radio influence voltages obtained with conventional type suspension apparatus and with my improved suspension apparatus.

Referring now to the drawing for a better understanding of my invention, my improved suspension apparatus comprises a downwardly opening body I having a convexly curved outer surface 11. Suitable recesses 12 are provided in the downwardly opening body, as shown in FIG. 1, for receiving attachment fittings 13 for a string of suspension insulators indicated generally at 25. While I show two strings of suspension insulators in the drawings, it will be apparent that one such string of suspension insulators may be employed.

Extending inwardly of the under surface of the downwardly opening body 10 adjacent opposite sides of each opening 12 are lugs 14 having aligned openings '16 therein which are disposed to register with a transverse opening 17 provided in one end of the insulator attachment fitting 13. Passing through the aligned openings 16 and 17 is a pin 1-8 which is held in position by suitable means, such as a cotter key 20.

'Depending from the inner surface of the downwardly opening body 10 adjacent opposite ends thereof are lugs 19 having openings 21 therethrough for receiving shackles 22 which in turn are operatively connected to conductor clamps indicated generally at 23. The lugs 19 are posigpedz inwardly of the sides of the body 10, as shown in As shown in FIG. 1, the conductors indicated at 24 are clamped in place by the conductor clamps 23 whereby they extend parallel and in spaced relation to eachother. Also, as shown in FIGS. 1 and 2, the downwardly opening body '10 is of a generally inverted U-shape, as viewed in cross section and the downwardly opening body extends transversely of and above the conductors 24. Preferably, an inverted V-shaped recess 26 is provided in the under surface of the downwardly opening body 10, as shown in FIG. 1 to simplify live line maintenance procedures and reinforcing beads 27 are provided along the lower edges of the body, as shown, to add strength to the composite body member.

In FIG. 3 ofthe drawing, I show the point at which corona extinction occurs where conventional flat type yoke members are employed and where my improved yoke member is employed. That is, with conventional flat type yoke members, corona extinction occurs at applied voltages below approximately 295 kilovolts, as shown at X in FIG. 3. With my improved yoke member, on the other hand, corona is extinct up to an applied voltage of approximately 445 kilovolts, as indicated at Y in FIG. 3. The curve 28 shows the radio influence voltages obtained with conventional type yoke members whereas the curve 29 shows the radio influence voltages obtained where my improved yoke member is employed. It will thus be seen that the assembly is protected against corona and radio influence voltages are decreased at relatively high line-to-ground voltages.

From the foregoing, it will be seen that I have devised improved suspension apparatus for conductors wherein the voltage distribution is more uniform throughout the insulator assembly whereby each unit of the insulator string carries more nearly equal portions of the total line-to-ground voltage thereby helping to prevent high electrical stresses on particular insulators. Also, by providing a relatively wide and convexly curved outer surface for the body of the yoke member, the assembly is relatively free from corona and radio influence voltages are decreased at relatively high line-to-ground voltages as compared with traditional yokes wherein the construction material is disposed in a flat plane. Furthermore, by providing a downwardly opening body member which is of a .generally inverted U-shape, as viewed in cross section, together with the other structural features of my improved body member, the yoke member has improved mechanical sterngth properties and rigidity as well as improved electrical properties.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited but is susceptible of various changes and modifications without departing from the spirit thereof, and I desire, therefore, that only such limitations shall 'be placed thereupon as are specifically set forth in the appended claims.

What I claim is:

1. In apparatus for suspending a conductor from an insulator attachment fitting comprising:

(a) a relatively wide downwardly opening shell-like body having a convexly curved outer surface,

(b) a pair of spaced apart lugs carried by and extending downwardly from the under surface of said body inwardly of the sides thereof, and wholly within the confines of said body,

(c) there being an opening through said body between said lugs of a size to receive one end of the insulator attachment fitting with the other end of said fitting extending outwardly of said convexly curved outer surface,

3 4 (d) there being aligned openings through said lugs 4. Apparatus for suspending a conductor from an inand said one end of said insulator attachment fitting, sulator attachment fitting as defined in claim 1 in which (e) a pin wholly within the confines of said body eX- the downwardly opening body is elongated and extends tending through said aligned openings and connecttransversely of the conductor receiving recess in said ing said insulator attachment fitting to said body, 5 conductor supporting clamps. (f) a lug depending from the under surface of said body inwardly of the sides thereof, and References Cited y the Examiner (g) a conductor supporting clamp operat-ively con- UNITED STATES PATENTS nected to said lug and having a conductor receiving recess therein. 10 2,086,150 7/1937 Austin. 2. Apparatus for suspending a conductor from an in- FOREIGN PATENTS SUIBIOI' attachment fitting as defined in claim 1 in Germany. the downwardly opening body is of a generally inverted U-shape as viewed in cross section. OTHER REFERENCES Apparatus for suspending 3 Conduct)? m an 15 Ohio Brass Advertisement, Electrical World, vol. 161, sulator attachment fitting as defined in claim 1 in which NO 12 March 23 19 4 page 29 a plurality of conductor supporting clamps are carried by said body to support conductors in spaced relation to LARAMIE E. ASKIN, Primary Examiner. each other. 

1. IN APPARATUS FOR SUSPENDING A CONDUCTOR FROM AN INSULATOR ATTACHMENT FITTING COMPRISING: (A) A RELATIVELY WIDE DOWNWARDLY OPENING SHELL-LIKE BODY HAVING A CONVEXLY CURVED OUTER SURFACE, (B) A PAIR OF SPACED APART LUGS CARRIED BY AND EXTENDING DOWNWARDLY FROM THE UNDER SURFACE OF SAID BODY INWARDLY OF THE SIDES THEREOF, AND WHOLLY WITHIN THE CONFINES OF SAID BODY, (C) THERE BEING OPENING THROUGH SAID BODY BETWEEN SAID LUGS OF A SIZE TO RECEIVE ONE END OF THE INSULATOR ATTACHMENT FITTING WITH THE OTHER END OF SAID FITTING EXTENDING OUTWARDLY OF SAID CONVEXLY CURVED OUTER SURFACE, (D) THERE BEING ALIGNED OPENINGS THROUGH SAID LUGS AND SAID ONE END OF SAID INSULATOR ATTACHMENT FITTING, (E) A PIN WHOLLY WITHIN THE CONFINES OF SAID BODY EX- 